ESP-8266 stopped working due to possibly faulty perfboard layout

Question

I have been following this tutorial to set up my ESP8266. I have also recreated on a perfboard the circuit provided in the tutorial, and I intend to use this perfboard circuit in my project.

The problem arises when I plug my ESP into the perfboard and try to talk to it through the serial monitor. When using a baud rate of 115200, the ESP responds to commands but in a garbled format. Also, the blue LED stays on after powerup for increasingly long periods of time. Now the blue LED is always on and the ESP no longer responds to any commands, except when reset and asked for the startup firmware info. I suspect that the ESP is now broken but am not sure how to check.

Also note that the ESP was working fine on a breadboard at 9600 baud, prior to the blue LED incident. Now it won't work with the breadboard either.

All commands were sent with newline and carriage return.

Is the ESP8266 broken? Could there be something wrong with my perfboard circuit? The circuit is rather dense and contains wiring for several other components in addition to the ESP-8266.

Answer 1

It turns out the real culprit was the AT+IPR=9600 command bricking the board. The board was "fixed" by obtaining the firmware and flashing it to the board using esptool.py. Download the repo's source code, navigate to the directory bin/at/, and see the file README.md to see which addresses to flash the different parts to.